Laboratory manual for the evaluation of non-automatic weighing devices

LG-3.20 Endurance (permanence) test

Table of contents


Reference

Sections 9, 10, 11, 12, 13, 14, 15, 16, and 21 of the Specifications Relating to Non Automatic Weighing Devices (1998)

Application

This test is intended for any complete mechanical or electronic weighing devices and for any weighing elements tested separately. Devices are subjected to the repetitive loading and unloading of specific loads applied 100 000 times (capacities of up to 1 000 kg (2 000 lb)) or 300 times (capacities above 1 000 kg (2 000 lb)). The endurance test is performed after all other tests.

Settings

Procedure (capacities of up to 1 000 kg (2 000 lb))

The following test load shall be used:

  1. After having moved the device to the permanence testing bench, perform the test described in LG-3.21.
  2. Apply the test load 25 000 times; perform an increasing and decreasing load test and record the results.
  3. Apply the test load an additional 25 000 times; perform an increasing and decreasing load test and record the results.
  4. Apply the test load an additional 25 000 times; perform an increasing and decreasing load test and record the results.
  5. Apply the test load an additional 25 000 times.
  6. Perform a load discrimination test, an increasing and decreasing load test, an eccentricity test.
  7. Record the results.

Procedure (capacities above 1 000 kg (2 000 lb))

The following test load shall be used:

Load between ¼ and ½ of max

  1. After having moved the device to the permanence testing area, perform an increasing and decreasing test to ascertain that the device measures as close to zero error as possible. Re-calibrate the DUT as necessary.
  2. Apply the test load 300 times; perform an increasing and decreasing load test and record the results.
  3. Perform a load discrimination test, an increasing and decreasing load test, an eccentricity test.
  4. Record the results.

Procedure (For devices tested in the field)

  1. After having moved the device to the permanence testing area, perform an increasing and decreasing test to ascertain that the device measures as close to zero error as possible. Re-calibrate the DUT as necessary.
  2. Ensure that the device is sealed or that the audit trail is active so the device cannot be re-calibrated.
  3. The applicant is to provide proof that the required number of weighings (300 or 100,000) has been completed
  4. Perform an increasing and decreasing load test and record the results.
  5. Perform a load discrimination test, an increasing and decreasing load test, an eccentricity test.
  6. Record the results.

Interpretation of results

The device meets the requirements if all the results remain within the applicable limits of error.

Revision

Rev.1 (September 2009)
  • Procedure added for 300 weighings for devices with a capacity greater than 1000 kg
Rev. 2 (March 2010)
  • AZSM renamed to AZT
  • IZSM requirements altered
  • Test procedure altered to reference LG-3.21
Date modified: